Timing Chain: Service and Repair

Front Cover Bolt Locations:

Fig. 6 Timing Chain & Sprocket Removal:

REMOVE
1. Drain cooling system.
2. Disconnect battery ground cable.
3. Loosen accessory drive belt idler. Remove drive belt and water pump pulley.
4. Remove power steering pump mounting bracket retaining bolts. Leaving hoses connected, place pump/bracket assembly aside in a position to prevent fluid from leaking out.
5. If equipped with air conditioning, remove compressor front support bracket. Leave compressor in place.
6. Disconnect coolant bypass hose at water pump.
7. Disconnect heater hose at water pump.
8. Disconnect radiator upper hose at thermostat housing.
9. Disconnect coil wire from distributor cap and remove cap with secondary wires attached.
10. Remove distributor hold-down clamp and lift distributor out of the front cover.
11. Raise vehicle.
12. Remove crankshaft damper and pulley using Crankshaft Damper Remover T58P-6316-D and Vibration Damper Remover Adapter T82L-6316-B or equivalent.

NOTE: If the crankshaft pulley and vibration damper have to be separated, mark the damper and pulley so that they may be reassembled in the same relative position. This is important as the damper and pulley are initially balanced as a unit.

NOTE: If the crankshaft damper is being replaced, check to see if the original damper has balance pins installed. If so, new balance pins (6A328 or equivalent) must be installed on the new damper in the same position as the original damper. The crankshaft pulley (new or original) must also be installed in the same relative position as originally installed.

13. Remove oil filter.
14. Disconnect radiator lower hose at water pump.
15. Remove oil pan.

CAUTION: The front cover cannot be removed without lowering the oil pan.

16. Lower vehicle.
17. Remove front cover retaining bolts. It is not necessary to remove water pump.

CAUTION: Do not overlook the cover attaching bolt located behind the oil filter adapter. The front cover will break if pried upon and all retaining bolts are not removed.

18. Remove ignition timing indicator.
19. Remove front cover and water pump as an assembly.
20. Remove cover gasket and discard.
21. Remove camshaft bolt and washer from end of the camshaft.
22. Remove distributor drive gear.
23. Remove camshaft sprocket, crankshaft sprocket and timing chain. If crankshaft sprocket is difficult to remove, pry sprocket off shaft using a pair of large screwdrivers positioned on both sides of the sprocket.

Distributor Gear:

24. Remove chain tensioner assembly from front of cylinder block. This requires first pulling back on ratcheting mechanism and installing a pin through the hole in the bracket to relieve tension.

NOTE: The front cover contains the oil pump. If a new front cover is to be installed, remove the water pump and oil pump from the old front cover.

INSTALL

NOTE: Lightly oil all bolt and stud threads before installation except those specifying special sealant.

1. Clean all gasket surfaces on the front cover, cylinder block and fuel pump. If reusing the front cover, replace crankshaft front oil seal.
2. If a new front cover is to be installed:
a. Install oil pump.
b. Clean water pump gasket surface. Position a new water pump gasket on the front cover and install water pump. Install pump retaining bolts. Tighten to 20-30 Nm (15-22 ft lb).

3. Rotate crankshaft as necessary to position piston No.1 at TDC and crankshaft keyway at the 12 o'clock position.
4. Install tensioner assembly. Make sure the ratcheting mechanism is in the retracted position with the pin pointing outward from the hole in the bracket assembly. Tighten retaining bolts to 8-14 Nm (6-10 ft lb).
5. Lubricate timing chain with engine oil. Install camshaft sprocket, crankshaft sprocket and timing chain.
6. Remove pin from tensioner assembly. Ensure timing marks on sprockets are positioned across from each other.

Timing Gear Alignment:

7. Install distributor drive gear.
8. Install bolt and washer assembly at end of camshaft and tighten to 40-50 Nm (30-37 ft lb).
9. Lubricate crankshaft front oil seal with clean engine oil.
10. Position a new cover gasket on the cylinder block and install the front cover\water pump assembly using dowels for proper alignment.

NOTE: Gasket and Trim Adhesive D7AZ-19B508-AA or equivalent is recommended to hold the gasket in position while the front cover is installed.

11. Position ignition timing indicator.
12. Install the front cover retaining bolts. Install the capscrew (Part No. N604841) nearest the oil filter flange last and tighten last. Apply Loctite or equivalent to bolt prior to installation. Tighten all bolts to 20-30 Nm (15-22 ft lb).
13. Raise vehicle.
14. Install oil pan.
15. Connect radiator lower hose. Tighten clamp securely.
16. Install oil filter.
17. Coat crankshaft damper sealing surface with clean engine oil.
18. Position crankshaft pulley key in the crankshaft keyway.
19. Install the damper using Damper Front Cover Seal Installer T82L-6316-A or equivalent.
20. Install damper washer and retaining bolt. Tighten bolt to 140-180 Nm (104-132 ft lb).
21. Install crankshaft pulley. Tighten retaining bolts to 26-38 Nm (19-28 ft lb).
22. Lower vehicle.
23. Connect coolant bypass hose. Tighten clamp securely.
24. Install distributor with rotor pointing at No. 1 distributor cap tower.
25. Install distributor cap and coil wire.
26. Connect radiator upper hose at thermostat housing. Tighten clamp securely.
27. Connect heater hose. Tighten clamp securely.
28. If equipped with air conditioning, install compressor and mounting brackets. Tighten attaching bolts to specification.
29. Install power steering pump and mounting brackets. Tighten retaining bolts to specification.
30. Position accessory drive belt over the pulleys.
31. Install water pump pulley.
32. Position accessory drive belt over water pump pulley and tighten the belt.
33. Connect battery ground cable.
34. Fill crankcase to proper level with specified oil.
35. Fill cooling system with specified coolant.

CAUTION: This engine has an aluminum cylinder head and requires a special unique corrosion inhibited coolant formulation to avoid radiator damage.

36. Start engine and check for coolant, oil or fuel leaks.
37. Check ignition timing and curb idle speed, adjust as required. Tighten distributor holddown bolt to 27-40 Nm (20-29 ft lb).
38. Install air cleaner assembly and air intake duct.